Stock-Based Compensation - Restricted Stock Activity, Unrecognized Costs (Details) - 2014 Plan - Restricted stock - USD ($)	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018
Restricted stock award activity
Unvested balance (in shares)	10,500	108,730
Granted (in shares)	8,600	10,500
Vested (in shares)	(10,500)	(108,730)
Unvested balance (in shares)	8,600	10,500
Weighted Average Grant Date Fair Value
Unvested balance (in dollars per share)	$ 11.86	$ 1.65
Granted (in dollars per share)	4.42	11.86
Vested (in dollars per share)	11.86	1.65
Unvested balance (in dollars per share)	$ 4.42	$ 11.86
Unrecognized compensation expense related to unvested awards	$ 6,984
Recognition period for compensation costs	1 year 26 days
Unvested restricted stock awards expected to vest (in shares)	3,600

Weighted-average period over which cost not yet recognized is expected to be recognized for award under share-based payment arrangement, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Amount of cost to be recognized for nonvested award under share-based payment arrangement. Excludes share and unit options.

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The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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The weighted average fair value at grant date for nonvested equity-based awards issued during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

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The number of non-vested equity-based payment instruments, excluding stock (or unit) options, that validly exist and are outstanding as of the balance sheet date.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Per share or unit weighted-average fair value of nonvested award under share-based payment arrangement. Excludes share and unit options.

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The number of equity-based payment instruments, excluding stock (or unit) options, that vested during the reporting period.

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The weighted average fair value as of grant date pertaining to an equity-based award plan other than a stock (or unit) option plan for which the grantee gained the right during the reporting period, by satisfying service and performance requirements, to receive or retain shares or units, other instruments, or cash in accordance with the terms of the arrangement.

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As of the balance sheet date, the number of shares into which expected to vest stock-based awards outstanding can be converted under the plan.

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